Chemical Reactions
What are the coefficients for the balanced equation below? __ HBr + __ Zn -> __ ZnBr₂ + __ H₂
2 // 1 // 1 // 1
1 // 1 // 1 // 2
1 // 2 // 2 // 2
2 // 1 // 2 // 1
The molecular formula for glucose is C6H12O6; what is its empirical formula?
CH20
C6H10O5
C6H14O7
C12H22O11
What are the coefficients for the balanced equation below? __ C₂H₅S + __ O₂ -> __ CO₂ + __ H₂O + __ SO₂
4 // 19 // 8 // 12 // 4
2 // 9 // 8 // 10 // 4
2 // 8 // 4 // 5 // 2
4 // 17 // 8 // 10 // 4
Which notation correctly represents a single replacement reaction?
A + BC → B + AC
A2B + C → A2C + B
AB + CD → AD + CB
AB → A + B
How does increasing pressure by decreasing volume influence shift direction within a closed system containing gaseous hydrogen iodide (HI) decomposing reversibly to form hydrogen (H₂) and iodine (I₂)?
A resultant expansion of the opposite phases is seen whereby larger quantities of halogens elements are generated at the expense of their combined diatomic counterpart, which stays minimally impacted due to the predominance of intermolecular forces at play here
No net displacement in either direction is witnessed since the overall particulate densities remain unaffected despite intensified molecular interactions in a tighter space
The equilibrium favors the formation of HI molecules with fewer total particles, thereby negating the effects of the raised pressurized environment created by reduced spatial constraints
There is an immediate doubling of the amounts of H₂ and I₂ present, subsequently reacting back to form even more of the original compound HI
In an exothermic reaction, what happens to energy?
It is released into the surroundings.
It is absorbed from the surroundings.
It converts solely into light energy.
It has no effect on the surroundings.
Which of the following best describes a key difference between complete ionic equations and net ionic equations?
Complete ionic equations show all soluble ionic compounds dissociated into ions, while net ionic equations only show the species that participate in the reaction.
Complete ionic equations include precipitates as ions, whereas net ionic equations do not.
Net ionic equations include spectator ions, but complete ionic equations do not.
Complete ionic equations represent only reactions in gas phase, while net ionic equations can represent reactions in any state of matter.

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What does "(aq)" after a chemical formula represent in a reaction equation?
Liquid form without any dissolving medium.
Aqueous solution, which means dissolved in water.
Solid state at room temperature.
Gaseous state at standard conditions.
For a hypothetical reversible process that reaches equilibrium quickly without external intervention, how would you describe its relationship between ∆Gº and Q?
Q has no bearing on ∆Gº as long as there are equal amounts reacting
When Q is lesser than K_eq (∆Gº becomes progressively more negative)
When Q equals K_eq (∆Gº = zero), indicating no net change over time
As Q increases beyond K_eq (∆Gº becomes increasingly more positive)
What is the term for the quantity of heat required to raise the temperature of one gram of water by one degree Celsius?
Electronvolt
Watt
Calorie
Joule